Reconstitution systems are known in the prior art. The systems typically include two components, a wet component and a dry component, which are mixed to form an injectable substance. The dry component is typically a lyophilized powder which contains one or more therapeutic agents. The wet component is a liquid diluent suitable for mixing with the dry component in forming a solution.
The dry component and the liquid component are maintained separately during storage. With a reconstitution cartridge or injector, the liquid and dry components are provided in the same cartridge or injection barrel with one or more seal elements being provided to separate the two components. Difficulties are encountered in the prior art in preparing such cartridges and injectors. In particular, the barrel of the cartridge or the injector is typically formed with a reduced-diameter distal, or patient, end configured to accommodate standard medical needle assemblies. The reduced-diameter distal end limits the ability to introduce the dry component in a dry state. There are limitations in the size of a stream of dry powder or the like being transmitted. The distal end of a typical cartridge or injector is too small to properly accept such a stream. The dry component is typically initially provided in a liquid form and introduced through the distal end of the barrel. The liquid is lyophilized in situ such that the dry component is produced in the device. The liquid form of the dry component is typically not introduced from the proximal end of the barrel since the liquid may leave residue along the barrel. This leads to not only potential loss of product but possible contamination issues.